Question

If the speed of the motorcycle is 40km/hr. how far will it travel in an hour and quarter?

Answer 1

Hint: It is given that the speed of the motorcycle is 40km/hr. This is nothing but the distance it covers in an hour is 40km. but we have to find the distance it covers in an hour and a quarter. That is one full hour and 15 minutes more. So let’s see!

Complete step by step solution:
Given that, a motorcycle has a speed of 40km/hr.
That is it covers a 40km distance in one hour.
We are asked to find the distance it covers in an hour and quarter.
So the total time will be more than an hour. That is, it travels a quarter hour more.
We know that 1 hour is 60 minutes.
So quarter hour will be \[\dfrac{{60}}{4} = 15\min utes\]
Now we need to find the distance it covers in these 15 minutes.
We will use a unitary method to do this.
So, in one hour it covers 40kms so in \[\dfrac{1}{4}\]hr it will cover, \[40 \times \dfrac{1}{4} = 10kms\]
Thus the total distance it covers is \[40 + 10 = 50kms\]
This is the total distance it will cover in one and a quarter hour.
So, the correct answer is “50k ms”.

Note: Note that, here the word quarter hour is most important. As we know, a quarter is one-fourth of a number. So one fourth of an hour is 15 minutes. Also note that if 40kms are divided into four equal parts each part will be of 10kms. Thus we can solve this problem orally.
Also note that, there is no need to convert km/hr into m/sec or any other units.